What if instead of wearing a watch, you had a light-up sensor thinner than your skin, taped to your hand, that would constantly tell you the time, temperature, and your vital signs?
You could simply glance down at your other hand to read your incoming messages.
It's a crazy futuristic idea, but researchers at the University of Tokyo are working to design such devices today.
They've developed thin-film electronic sensors that they call "e-skin."
The e-skin gets laminated onto your hand with clear, ultra-thin tape, where they showed it can project numbers and letters in different colors, and even measure your pulse and blood oxygen levels.
The researchers described the e-skin in an April 15 paper in the journal Science Advances.
They designed the e-skin in part because our smartphones are too bulky, one of the researchers, Takao Someya, said in a press release.
"What would the world be like if we had displays that could adhere to our bodies and even show our emotions or level of stress or unease?" Someya wondered. "In addition to not having to carry a device with us at all times, they might enhance the way we interact with those around us or add a whole new dimension to how we communicate."
Of course, this technology is a long way from getting out of the lab and onto your hands. It also raises a lot of questions that the researchers haven't answered in this study, like whether the laminated tape lets the skin breathe and if it's durable, comfortable, and safe.
Do we need to be constantly monitoring our pulse or blood oxygen levels? Is there any harm from taping electronics to our skin? Is this really better than a smartwatch (which itself is perhaps not better than a smartphone) — or is it just weirder? As with anything new and experimental, the researchers have a lot of work to do.
Who knows whether e-skin could actually ever replace your phone. But it's a cool concept nonetheless — and shows just how quickly we're becoming capable of creating technology we once could only imagine.
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